Blowpipe



July 3, 1934. s. R. OLDHAM ET!" AL BLOWPIPE Filed Oct. 11, 1930 INVENTORS.

2 Sheets-Sheet l July 3, 1934. s OLDHAM r AL 1,965,467

BLOWPI PE Filed Oct. 11, 1930 2 Sheets-Sheet 2 NVENTORS.

, v ATTORNEYS.

Patented July 3, 1934 UNITED V STATES BLOWPIPE Samuel R. Oldham, Chicago, Ill., and Lloyd W. Young, Buffalo, N. Y., assignors to The Oxweld- Railroad Service Company, a corporation of Delaware Application October 11, 1930, Serial No. 488,124

8 Claims.

Our invention relates to an improved blowpipe and more particularly to an improved injector type gas mixer which is adapted to accommodate nozzles of various sizes.

' In order to maintain the proper gas pressures and velocities in the orifices of blowpipe tips of various sizes, the usual practice is to provide each tip with a mixer built in the tip, or to use a series of mixers constructed as separate units to be inserted in the body or head of the blowpipe. The first of these methods adds to the-cost of the tips, while the second makes it necessary to carry extra equipment in the form of mixers, and entails loss of time in interchanging these mixers.

One of the objects of our invention is to provide a blowpipe with a composite gas mixerwhich has more than one mixing passage, and which may interchangeably employ one passage alone or more than one of said passages simultaneously to accommodate burner tips of various sizes.

Another object of our invention is to divide the gases in the mixer into one or more streams so that the velocity of the gas in each stream will be sufiiciently great to prevent backflres.

The above and other objects will be more clearly understood from the following description and drawings, in which:

Fig. I is a side view of the torch assembly.

Fig. II is a longitudinal section of the torch assembly. Fig. III is an exploded view of the gas mixer parts.

Figs. IV, V and VI are cross-sections of the mixer in different positions of adjustment on line IV'-IV in Fig. 11 looking in the direction of the torch tip, and

Figs. VII, VIII and IX are, respectively, crosssections of the mixer in different positions of adjustment on line VII-VII looking towards the handle and which sections correspond, respectively to the positions of adjustment shown in Figs. IV, V and VI. Fig. X is an enlarged cross section of the mixer plug on line X-X of Fig. III.

Our gas mixer 1 isadapted to be assembled in a cavity 2 in a blowpipe head 3 which is attached to a handle 4 having fuel gas such as acetylene supplied thereto through a hose connection 5 and having a combustionsupporting gas such as oxygen supplied thereto through another hose connection 6. The oxygen flows through a passage '7 in the handle 4 and through a passage 8 in the head 3 to a chamber 9 at the inner end of the mixer l. The flow of this gas through the passage 8 in the head is controlled by an oxygen valve The acetylene flows from the hose connection 5 through a passage 11 in the handle and through a passage 12 in the head 4 to a chamber 13 which communicates with a combining chamber 14 in the mixer l. The flow of acetylene to the mixer is controlled by a valve 15 in the acetylene passage 12.

The mixer comprises an inner plug 16, and an outer plug 17 which are separated by and are adapted to oscillate in unison on each side of a stationary washer 18. The washer 18 is fixed against rotation by a projection 19 thereon which is inserted in a recess in the head 3 and a truncated sector is removed therefrom to provide the gas combining chamber 14 for the mixer. The mixer plugs 16 and 17 and the spacing washer 18 are held in axial alignment bya centralizing pin 20 which extends into a central bore in each of the mixer plugs and through a central bore in the spacing washer 18. The mixer plugs 16 and 17 are caused to oscillate in unison about the axis of the centralizing pin 20 by an eccentric locating pin 21 which extends from a bore in one mixer plug 16, through the combining chamber 14 and into an aligned bore in the other mixer plug The inner mixer plug 16 is provided with a shoulder.22 which fitsagainst an annular ledge 23 within the end of the cavity in the head 3 and maintains the innermost end of the plug spaced from the end of the cavity 2 in the head 3 to form the oxygen chamber 9. A plurality of passages or injector nozzles 24 are provided in the inner plug 16 to allow the oxygen to flow from the oxygen chamber -9 to the combining chamber 14. As shown in Fig. X, the passages 24 may be made of d fferent size in order to obtain a greater number of graduations in the volume of gas delivered by the mixer with the use of a given number of injector passages. The outer plug 17 is provided with an equal number of mixing passages 25 which are axially aligned with the oxygen passages in the other plug 16. The plug is also provided with an arcuate beveled edge 26 to facilitate the passage of the acetylene into the combining chamber 14 when the mixer is in any of its positions of adjustment which will be referred to infra. The oxygen is discharged into the combining chamber 14 between the mixer plugs at a high velocity and by its injector action draws the acetylene into the mixing passages 25. The mixed gases are delivered to a goose neck 27 and thence to the blowpipe tip 28.

The mixer is held in the head bya clamping nut 29 which rotatably fits over the goose neck 27and the outer mixer plug 17. The nut 29 is provided with external threads which cooperate with an internally threaded bore in the blowpipe head cavity 2. The nut 29 may be screwed into the-threaded bore until its inner end comes into contact with an annular shoulder 30 on the outer mixer plug 17. The movement of the nut urges the two plugs together and towards the end of the cavity 2 in the blowpipe head 3.

The individual gas passages in the mixer 1 may be of the same size or varied in size and number to provide a set of holes each difiering in size in order to accommodate a number of blowpipe tips having difierent sizes of discharge orifices and in order to obtain the desired flamecharacteristic. As a specific example, the mixer shown herein is provided with three such gas passages, of which all, or only two may be employed simultaneously or one may be employed alone, as is respectively disclosed in Figs. IV to III. This mixer is designed to serve a set of seven blowpipe tips. When it is set in the position shown in Figs. IV and VII with all three gas passages in operation, it is adapted to serve the largest three of the seven tips, and when it is set in the position shown in Figs. V and VIII with two passages in operation, it is adapted to serve the next two smaller tips and when it is set in'the position shown in Figs. VI and IX with one passage in operation, it is adapted to serve the two smallest tips of the set.

The mixer 1 may be adjusted to the above mentioned positions by loosening the clamping nut 29 and turning the index arrow on the goose neck 27 until the arrow is positioned opposite one of the arrows A, B or C which indicate the respective positions of adjustment shown in Figs. IV, V and VI. The clamping nut 29 may be then tightened to retain the mixer 1 in the proper adjustment for the desired size of tips to be used.

While we have shown a singlemodification of our invention, we do not wish to be limited to the specific details shown, as they may be changed without departing from the scope of our invention as defined in the appended claims. For example, the mixer shown herein is provided with only three mixer passages which may be varied as to number and size. Also, the eccentric locating pin for causing the mixer plugs to rotate in unison may be dispensed with and as a substitute a square head on each end of the centralizing pin which may be adapted to fit in a square bore in each ofthe mixer plugs may be provided.

Furthermore, the spacing washer may be so perforated and the mixer passages may be so arranged in relationto the perforations, that each mixer passage may be used individually or in combination with any number of other passages.

We claim:

1. In a blowpipe, a gas mixer comprising a plurality of injectors of difierent size; and means for adjusting one or more of said injectors into an operative position.

2. In a blowpipe, a gas mixer of the injector" type comprising a plurality of injectors of different size and a valve adapted to maintain one or more of said injectors in'operation at one time.

3. A blowpipecomprising a head having a cavity therein; a gas mixer of the injector type located in said cavity, said mixer comprising a plurality of injectors of different size adapted to deliver, a mixture of gas to the blowpipe tip; means for operating one injector or more than one of said injectors at one time. I

4. In a blowpipe, a gas mixer of the injector type comprising a plurality of injectors, a stationary valve disc adapted to close and open said injector passages, means comprising a mixture passage stem for operating saidinjector passages to the closed and open positions on said valve.

'5. A blowpipe comprising a head having a cavity therein; a gas mixer of the injector type located in said cavity; said mixer comprising a plurality of injectors having separate injector nozzles and mixing passages adapted to deliver a mixture of gas to the blowpipe tip; means for maintaining in operation one injector or more than one of said injectors at one time;

6. In a blowpipe, a gas mixer of the injector type comprising a member located in a cavity in the blowpipe, said member having a plurality of injector nozzles therein adapted to be supplied with a gas from said cavity, a second member closing the outer end of said cavity, and separated from the first member, said second member having a plurality of mixing passages extending therethrough, the inlet to each mixing passage being in alignment with an injector nozzle outlet in said first member, a stationary valve disc positioned between said first and second members, said disc having a portion removed therefrom to provide a combining chamber for the gas discharged from said injector nozzles and another gas admitted to said chamber, a mechanical connection between said first and second members, means for operating said second member to operate both of said members in unison to place one or more of said injectors into operative position at one time.

7. In a blowpipe, a gas mixer of. the injector type comprising a plug having a plurality of high velocity passages therethrough; a second plug spaced from the first plug and adapted to be operated in unison therewith; said second plug having a plurality of larger gas passages therethrough of equal number to the gas passages in the first plug and having each of their inlets positioned opposite to the respective outlets of the first mentioned passages; and a valve interposed between said plugs for controlling the operation of said passages in each of said plugs.

8. A gas mixer of the injector type comprising a body having a plurality of passages for a gas at a high velocity, an equal number of mixing pas-. sages in axial alignment with the first mentioned passages, and a combining chamber interposed between each of the discharge and inlet ends of said passages; and a valve adapted to maintain one or more of said first mentioned passages in an open or closed position of adjustment.

SAMUEL R. OLDHAM. LLOYD W. YOUNG. 

